#define _CRT_SECURE_NO_WARNINGS 1
#include<iostream>
#include<vector>
using namespace std;
int takeAttendance(vector<int>& records)
{
    int left = 0, right = records.size() - 1;
    while (left < right)
    {
        int mid = left + (right - left) / 2;
        if (records[mid] == mid)
            left = mid + 1;
        else
            right = mid;


    }
    return records[left] == left ? left + 1 : left;
}
int main()
{
	return  0;
}